Free energy profile of the substrate-induced occlusion of the human serotonin transporter.

The serotonin transporter (SERT) is a member of the Solute Carrier 6 (SLC6) family and is responsible for maintaining the appropriate level of serotonin in the brain. Dysfunction of SERT has been linked to several neuropsychiatric disorders, including depression, anxiety and obsessive-compulsive disorder. Therefore, an in-depth understanding of the mechanism on an atomistic level, coupled with a quantification of transporter dynamics and the associated free energies is required. Here, we constructed Markov state models (MSMs) from extensive unbiased molecular dynamics simulations to quantify the free energy profile of serotonin (5HT) triggered SERT occlusion and explored the driving forces of the mechanism of occlusion. Our results reveal that SERT occludes via multiple intermediate conformations and show that the motion of occlusion is energetically downhill for the 5HT-bound transporter. Force distribution analyses show that the interactions of 5HT with the bundle domain are crucial. During occlusion, attractive forces steadily increase and pull on the bundle domain, which leads to SERT occlusion. Some interactions become repulsive upon full occlusion, suggesting that SERT creates pressure on 5HT to promote its movement towards the cytosol.

Diacylglycerols interact with the L2 lipidation site in TRPC3 to induce a sensitized channel state.

Coordination of lipids within transient receptor potential canonical channels (TRPCs) is essential for their Ca2+ signaling function. Single particle cryo-EM studies identified two lipid interaction sites, designated L1 and L2, which are proposed to accommodate diacylglycerols (DAGs). To explore the role of L1 and L2 in TRPC3 function, we combined structure-guided mutagenesis and electrophysiological recording with molecular dynamics (MD) simulations. MD simulations indicate rapid DAG accumulation within both L1 and L2 upon its availability within the plasma membrane. Electrophysiological experiments using a photoswitchable DAG-probe reveal potentiation of TRPC3 currents during repetitive activation by DAG. Importantly, initial DAG exposure generates a subsequently sensitized channel state that is associated with significantly faster activation kinetics. TRPC3 sensitization is specifically promoted by mutations within L2, with G652A exhibiting sensitization at very low levels of active DAG. We demonstrate the ability of TRPC3 to adopt a closed state conformation that features partial lipidation of L2 sites by DAG and enables fast activation of the channel by the phospholipase C-DAG pathway.

Microstructural Pattern Formation during Far-from-Equilibrium Alloy Solidification.

We introduce a new phase-field formulation of rapid alloy solidification that quantitatively incorporates nonequilibrium effects at the solid-liquid interface over a very wide range of interface velocities. Simulations identify a new dynamical instability of dendrite tip growth driven by solute trapping at velocities approaching the absolute stability limit. They also reproduce the formation of the widely observed banded microstructures, revealing how this instability triggers transitions between dendritic and microsegregation-free solidification. Predicted band spacings agree quantitatively with observations in rapidly solidified Al-Cu thin films.

Perceptions and Experiences of High-Intensity Interval Training in Kidney Transplant Recipients: A Big HIIT?

High-intensity interval training (HIIT) is considered a novel and time-efficient method to reduce cardiovascular disease risk, a leading cause of mortality in kidney transplant recipients. However, research in this population is severely limited. The aim of this study was to understand kidney transplant recipients' perceptions and experiences of HIIT and their readiness to participate in HIIT. Individual, semi-structured interviews were conducted in adults with a kidney transplant (n = 13; 53±13 years). Interviews were audiorecorded, transcribed verbatim, and subjected to framework analysis. Overall, participants had a good knowledge of HIIT and were open to participation. Acknowledgment of the superior benefits to cardiovascular, mental, and general health, as well as the lower time commitment, were all motivators for participation. There were some heightened concerns around damaging the kidney and 'knowing your limits. Personalization, physician's approval, and supervision were all important factors in participation. This study provides evidence that HIIT would be, in principle, largely accepted by recipients of a kidney transplant. However, several considerations are also identified in the present study, which would be essential to the success of any future efficacy trial or rehabilitation program.

Perceived barriers and facilitators to exercise in kidney transplant recipients: A qualitative study.

BACKGROUND: Exercise has the potential to attenuate the high levels of cardiovascular morbidity and mortality present in kidney transplant recipients (KTRs). Despite this, activity levels in KTRs remain low. The aim of this qualitative study was to explore the barriers and facilitators of exercise in KTRs. METHODS: Thirteen KTRs (eight males; mean ± SD; age 53 ± 13 years; estimated glomerular filtration rate 53 ± 21 ml/min/1.73 m2 ) were recruited and completed semistructured one-to-one interviews at University Hospitals of Leicester NHS Trust. All KTRs were eligible if their kidney transplant was completed >12 weeks before interview and their consultant considered them to have no major contraindications to exercise. All interviews were audio recorded, transcribed verbatim and subject to framework analysis to identify and report themes. RESULTS: Themes were organized into personal, behavioural and environmental factors based on social cognitive theory. Facilitators of exercise were largely internal: enjoyment, exercise for general health and health of the transplanted kidney and desire to maintain normality. Social interaction, support and guidance of healthcare professionals and goal setting were perceived as motivational. Harming the kidney, a lack of guidance, self-motivation and accessibility were barriers to exercise. CONCLUSION: These results provide detailed insight into the development of interventions designed to increase physical activity in KTRs. They provide strong evidence that specific exercise guidelines are required for this population and that the healthcare system could have a key role in supporting KTRs to become more physically active. Interventions need to be multifaceted to appeal to the differing levels of support desired by KTRs. PATIENT OR PUBLIC CONTRIBUTION: KTRs were involved in the development of the interview topic guide to ensure all relevant topics were explored.

Prevalence and correlates of physical activity across kidney disease stages: an observational multicentre study.

BACKGROUND: People with chronic kidney disease (CKD) report high levels of physical inactivity, a major modifiable risk factor for morbidity and mortality. Understanding the biological, psychosocial and demographic causes of physical activity behaviour is essential for the development and improvement of potential health interventions and promotional initiatives. This study investigated the prevalence of physical inactivity and determined individual correlates of this behaviour in a large sample of patients across the spectrum of kidney disease. METHODS: A total of 5656 people across all stages of CKD (1-2, 3, 4-5, haemodialysis, peritoneal dialysis and renal transplant recipients) were recruited from 17 sites in England from July 2012 to October 2018. Physical activity was evaluated using the General Practice Physical Activity Questionnaire. Self-reported cardiorespiratory fitness, self-efficacy and stage of change were also assessed. Binominal generalized linear mutually adjusted models were conducted to explore the associations between physical activity and correlate variables. This cross-sectional observational multi-centre study was registered retrospectively as ISRCTN87066351 (October 2015). RESULTS: The prevalence of physical activity (6-34%) was low and worsened with disease progression. Being older, female and having a greater number of comorbidities were associated with greater odds of being physically inactive. Higher haemoglobin, cardiorespiratory fitness and self-efficacy levels were associated with increased odds of being active. Neither ethnicity nor smoking history had any effect on physical activity. CONCLUSIONS: Levels of physical inactivity are high across all stages of CKD. The identification of stage-specific correlates of physical activity may help to prioritize factors in target groups of kidney patients and improve the development and improvement of public health interventions.

Feasibility, acceptability and effect of the Mindful Practice curriculum in postgraduate training of general practitioners.

BACKGROUND: Early career general practitioners are known to be at high risk of burnout. There is a need for widely applicable, cost-effective evidence-based interventions to develop trainees' protective skills and strategies. RESULTS: Of 120 eligible trainees, 23 (19.2%) expressed interest in participating, 17 subsequently started the course, and 15 completed at least 5 out of its 6 sessions. All psychological measures were stable for the six-week period prior to commencing the course. Following the course, there were statistically significant (p < 0.05) improvements in wellbeing, resilience, mindfulness, emotional exhaustion, disengagement, and stress scores. Participants described numerous benefits, and most stated that they would recommend it to colleagues. CONCLUSION: Including mindful practice within general practice vocational training is feasible, and in this study it benefited the psychological wellbeing of participants. Further research is needed to explore ways of increasing uptake and course completion, the sustainability of its effects, and the wider applicability of this approach.

Microstructure and Thickness Effects on Impact Behavior and Separation Formation in X70 Pipeline Steel.

In an effort to optimize the transportation of oil and gas, the pipeline industry is developing large-diameter, thick-walled pipelines that can withstand low temperatures and high pressures. In this study, three X70 steel plates of similar chemistry, ranging in thickness from 13.5 mm to 22 mm, were subjected to drop-weight tear and Charpy V-notch tests to determine the effects of plate thickness and microstructure on the formation of separations and impact behavior. Constraint induced by specimen thickness appears to dictate the location of separations, the three microstructures exhibited different separation behaviors, and microstructural banding was not found to promote separation formation. Separations were most frequent when the primary fracture plane was parallel to the rolling direction. This study also found that standardized empirical relationships between Charpy V-notch and drop-weight tear tests do not estimate to the advanced high-strength and -toughness steels investigated.

Promoting integrated care in prostate cancer through online prostate cancer-specific holistic needs assessment: a feasibility study in primary care.

PURPOSE: This study assessed the feasibility of implementing a novel model of integrated prostate cancer care involving an online prostate cancer-specific holistic needs assessment (sHNA) and shared digital communication between patients and their healthcare professionals (HCPs). The sHNA produces a semi-automated care plan that is finalised in consultation between the patient and their practice nurse. METHODS: Men living with and beyond prostate cancer were invited to participate in a 9-month non-randomised cluster controlled feasibility study. The intervention group was asked to complete the sHNA on three occasions. Data were collected using Patient Reported Outcome Measures (PROMs) at baseline, 10 and 24 weeks, and 9 months. Outcomes included recruitment, retention, acceptability, and engagement with the sHNA and PROMs. RESULTS: Fourteen general practices (8 intervention and 6 control), and 41 men (29 intervention and 12 control) participated. Initial patient engagement with the sHNA was high, with all but one receiving practice nurse-led follow-up and an individualised care plan. The sHNA proved useful in identifying 'red flag' symptoms, and helping practice nurses decide when to seek further medical care for the patients. There was a high level of acceptability for patients and HCPs. However, integration of care did not occur as intended because of problems linking hospital and general practice IT systems. CONCLUSION: While the study demonstrated the feasibility of implementing the sHNA, it did not meet the a priori progression criteria; as such, undertaking a definitive randomised controlled trial is not appropriate until the identified methodological and technical issues have been addressed.

Barriers and facilitators for engagement and implementation of exercise in end-stage kidney disease: Future theory-based interventions using the Behavior Change Wheel.

Theory-driven interventions are required to increase the adoption and implementation of physical activity and exercise programs among patients with ESKD. The Behavior Change Wheel (BCW) represents a synthesis of behavior change theories and can be used to aid the systematic development of theory-driven interventions designed to change exercise behavior. The goal of this review was to synthesize barriers and facilitators to engagement and implementation of exercise and develop theory-based recommendations for exercise behavior change interventions in patients with ESKD. We applied the BCW in the current context of exercise for ESKD patients and conducted an analysis of patients' and health care professionals' (HCPs) capabilities, opportunities, and motivations to engage or promote exercise, respectively. Our analysis identified a number of salient barriers that could be targeted via intervention to increase levels of physical activity and exercise. Intervention functions identified as most likely to change patient behavior included training, enablement, education, restructuring environment, persuasion, modeling, incentivizing, and coercion. Similarly, intervention functions most likely to change HCPs behavior for exercise promotion included training, modeling, education, environmental restructuring, persuasion, and incentivizing. We also considered potential over-arching policy changes required to support these interventions. Our findings provide theory-based recommendations that can help inform future clinical and research decision-making for implementing exercise interventions in these patients. However, high-quality research in this area is desperately needed to ensure that interventions not only be theory-driven, but evidence-based.

"My gut feeling is we could do more..." a qualitative study exploring staff and patient perspectives before and after the implementation of an online prostate cancer-specific holistic needs assessment.

BACKGROUND: Men surviving prostate cancer report a wide range of unmet needs. Holistic needs assessments (HNA) are designed to capture these, but are traditionally paper-based, generic, and only carried out in secondary care despite national initiatives advocating a "shared care" approach. We developed an online prostate cancer-specific HNA (sHNA) built into existing IT healthcare infrastructure to provide a platform for service integration. Barriers and facilitators to implementation and use of the sHNA were explored from both the patients and healthcare professionals (HCPs) perspectives. METHODS: This qualitative study consisted of two phases. Phase 1 used semi-structured interviews to explore HCPs (n = 8) and patients (n = 10) perceptions of the sHNA, prior to implementation. Findings were used to develop an implementation strategy. Phase 2 used semi-structured interviews to explore HCPs (n = 4) and patients (n = 7) experienced barriers and motivators to using the sHNA, 9 to 12 months after implementation. Interviews were audio-recorded, transcribed verbatim and thematically analysed. Themes were mapped to the Theoretical Domains Framework. RESULTS: HCPs and patients anticipated many benefits from using the sHNA. Barriers to implementation included: confidence to work in depth with prostate cancer patients, organisational and cultural change, and patient factors. Our implementation strategy addressed these barriers by the provision of disease specific training delivered in part by a clinical nurse specialist; and a peer-led IT supporter. Following implementation HCPs and patients perceived the sHNA as beneficial to their practice and care, respectively. However, some patients experienced barriers in using the sHNA related predominately to symptom perception and time since treatment. HCPs suggested minor software refinements. CONCLUSIONS: This work supports the importance of identifying barriers and motivators to implementation, and using targeted action via the development of an implementation strategy to address these. Whilst this process should be on-going, undertaking this work at an early stage will help to optimise the implementation of the sHNA for future trials.

Twelve-week combined resistance and aerobic training confers greater benefits than aerobic training alone in nondialysis CKD.

There is a growing consensus that patients with chronic kidney disease (CKD) should engage in regular exercise, but there is a lack of formal guidelines. In this report, we determined whether combined aerobic and resistance exercise would elicit superior physiological gains, in particular muscular strength, compared with aerobic training alone in nondialysis CKD. Nondialysis patients with CKD stages 3b-5 were randomly allocated to aerobic exercise {AE, n = 21; 9 men; median age 63 [interquartile range (IQR) 58-71] yr; median estimated glomerular filtration rate (eGFR) 24 (IQR 20-30) ml·min-1·1.73 m-2} or combined exercise [CE, n = 20, 9 men, median age 63 (IQR 51-69) yr, median eGFR 27 (IQR 22-32) ml·min-1·1.73 m-2], preceded by a 6-wk run-in control period. Patients then underwent 12 wk of supervised AE (treadmill, rowing, or cycling exercise) or CE training (as AE plus leg extension and leg press exercise) performed three times per week. Outcome assessments of knee extensor muscle strength, quadriceps muscle volume, exercise capacity, and central hemodynamics were performed at baseline, following the 6-wk control period, and at the end of the intervention. AE and CE resulted in significant increases in knee extensor strength of 16 ± 19% (mean ± SD; P = 0.001) and 48 ± 37% ( P < 0.001), respectively, which were greater after CE ( P = 0.02). AE and CE resulted in 5 ± 7% ( P = 0.04) and 9 ± 7% ( P < 0.001) increases in quadriceps volume, respectively ( P < 0.001), which were greater after CE ( P = 0.01). Both AE and CE increased distance walked in the incremental shuttle walk test [28 ± 44 m ( P = 0.01) and 32 ± 45 m ( P = 0.01), respectively]. In nondialysis CKD, the addition of resistance exercise to aerobic exercise confers greater increases in muscle mass and strength than aerobic exercise alone.

Motivations and barriers to exercise in chronic kidney disease: a qualitative study.

BACKGROUND: Exercise has the potential to modulate a number of complications associated with chronic kidney disease (CKD). However, typically, CKD patients lead very sedentary lifestyles, the reasons for which are not fully known. The aim of this qualitative study was to gain an understanding of the motivators, barriers and beliefs held by CKD patients regarding exercise. METHODS: We conducted 3 focus groups and 22 semi-structured interviews. Data were collected from nephrology outpatient clinics in the United Kingdom. A total of 36 individuals with CKD stages 1-5 not requiring renal replacement therapy, aged 26-83 years participated in this study. This manuscript outlines the findings from patients with CKD stages 3-5. Focus groups and interviews were transcribed verbatim and analysed thematically. RESULTS: Positive attitudes to exercise reflected autonomous motivations including: exercising for health; enjoyment and social interaction. Family support and goal setting were seen as motivators for exercise and the accessibility of local facilities influenced activity levels. Barriers to exercise were poor health, fear of injury or aggravating their condition, a lack of guidance from healthcare professionals and a lack of facilities. CONCLUSIONS: These findings are an important first stage in the development of a CKD-specific exercise behaviour change intervention. Interventions should operate at multiple levels, with a focus on improving patient autonomy and exercise self-efficacy, support networks and the physical environment (e.g. the accessibility of local facilities). In addition, strategies are required to ensure that the healthcare system is actively promoting and routinely supporting exercise for all patients with CKD.

Beyond the Binary: The Issue of Intra-Minority Hostility and the Need to Challenge Conventional Victim/Perpetrator Frameworks Within Hate Studies.

It is well-established within the hate studies literature that the majority of hate crimes and incidents of targeted hostility are perpetrated by those in the "majority" society. In the UK, academic and official research consistently shows that young White, British males are most commonly the culprits of all forms of targeted victimization, especially racist hate. However, urban areas of "super-diversity" offer researchers an opportunity to understand hate crime victimization and perpetration in a more nuanced and comprehensive way. Hate studies research has slowly begun to highlight instances of people from marginalized and stigmatized groups being targeted on the basis of their identity by individuals who are also members of minority groups, sometimes even the same minority group as the victim. Very little is understood about this particular victimizing dynamic other than it appears to be an attempt by minority group members to "fit in" by adopting what they perceive to be majority group values and attitudes. By drawing from 44 qualitative in-depth interviews exploring the experiences of new migrants and refugees and observations from 20 months of grassroots engagement, this article challenges established theories of "othering" that overwhelmingly refer to binary, static majority/minority tensions. The stories of these too-often "hidden" victims of targeted hostility offer a fresh perspective on the relationships between victims of hate and perpetrators. The article also contributes new explanations as to why those who are often targeted go on to target others.

A Practical Guide to Identify Patients With Multifocal Motor Neuropathy, a Treatable Immune-Mediated Neuropathy.

Multifocal motor neuropathy (MMN) is a rare immune-mediated motor neuropathy characterized by asymmetric weakness that preferentially affects distal upper limb muscles. The clinical features of MMN may be difficult to differentiate from motor neuron disease. Other conditions that may be mistaken for MMN include inclusion body myositis, chronic inflammatory demyelinating polyradiculoneuropathy, hereditary neuropathy with liability to pressure palsy, focal neuropathies, and radiculopathies. A key distinguishing electrophysiologic feature of MMN is the motor nerve conduction block located at noncompressible sites. MMN is a treatable neuropathy; therefore it is important that primary care physicians are aware of the features of the disease to identify potential patients and make referrals to a neuromuscular specialist in a timely manner. This review provides an overview of the disease, highlights key differential diagnoses, and describes available treatment options for patients with MMN.

Probing binding and occlusion of substrate in the human creatine transporter-1 by computation and mutagenesis.

In chordates, energy buffering is achieved in part through phosphocreatine, which requires cellular uptake of creatine by the membrane-embedded creatine transporter (CRT1/SLC6A8). Mutations in human slc6a8 lead to creatine transporter deficiency syndrome, for which there is only limited treatment. Here, we used a combined homology modeling, molecular dynamics, and experimental approach to generate a structural model of CRT1. Our observations support the following conclusions: contrary to previous proposals, C144, a key residue in the substrate binding site, is not present in a charged state. Similarly, the side chain D458 must be present in a protonated form to maintain the structural integrity of CRT1. Finally, we identified that the interaction chain Y148-creatine-Na+ is essential to the process of occlusion, which occurs via a "hold-and-pull" mechanism. The model should be useful to study the impact of disease-associated point mutations on the folding of CRT1 and identify approaches which correct folding-deficient mutants.

Understanding patient demand for and use of antibiotics for upper respiratory tract infection: A qualitative application of the Necessity-Concerns Framework in Saudi Arabia.

Background: Reducing antimicrobial resistance (AMR) is a priority for public health. Inappropriate patient demand is an important driver of unnecessary antibiotic use. To develop an effective intervention to reduce inappropriate demand for antibiotics in upper respiratory tract infections (URTIs), it is important to identify patient perceptions that influence demand for, and appropriate use of antibiotics. Aim: To identify and describe the beliefs about antibiotics necessity and concerns that patients with URTIs have, in Riyadh, Saudi Arabia. Method: An exploratory qualitative approach was used. One-to-one, face-to-face or telephone semi-structured interviews were conducted with participants recruited using purposive sampling (based on age and gender) from primary healthcare centre in Riyadh, Saudi Arabia were conducted. Only adult patients who currently experience URTIs symptoms and agreed to participate were recruited. Recruitment for interviews continued until data saturation point was reached. The interview guide explored patients' necessity beliefs and concerns about antibiotics, AMR perceptions, and expectations from URTIs consultation. Interview transcripts were coded using QSR NVivo 12 using framework analysis informed by the Necessity-Concerns Framework to identify key motivations driving antibiotic requests and consultations. Results: the study interviewed 32 participants (44% were male, average age was 36.84). Results identified that the patients often relate their personal need for antibiotics when encountering an URTIs symptoms to the type, severity and duration of symptoms. Patients also linked antibiotics with quicker recovery, generally expressing few concerns about antibiotics mainly because of its short duration of use. However, some conveyed their concern about frequent administration of antibiotics and effect on the body's immune system function, which may make them more prone to infections in the future. Participants varied widely in their awareness of AMR; this was associated with many misconceptions, such as confusing AMR with antibiotics efficacy and tolerance. Interestingly, the interplay between necessity beliefs and concerns was observed to influence the decision to start and stop antibiotic, potentially impacting inappropriate antibiotic demand and unnecessary use. Conclusion: This study highlighted important beliefs and misconceptions about antibiotics and AMR in Saudi population which can be targeted in future interventions to reduce inappropriate demand for antibiotics and optimise appropriate usage.